Syria’s Aleppo University on Thursday announced it was suspending classes after pro-government forces killed four students and arrested more than 200 in a campus raid during anti-regime protests.

In a message posted on its website, the northern city’s university told students that classes were suspended until final exams on May 13.

“Students were barred from entering the campus and were told that the university dorms were shut down until further notice,” Mohammed al-Halabi, an activist on the ground, told AFP via Skype.

He said security forces had raided the dormitories Thursday morning and had thrown out students and their belongings. He said some of the rooms were torched.

Student activist Thaer al-Ahmed said security forces and pro-regime gunmen fired tear gas and live ammunition to disperse the students at Aleppo University after entering the students’ residences late Wednesday night.

The decision to shut down the university came after Syrian troops and armed supporters overnight stormed an anti-regime protest on campus killing four students and arresting more than 200, according to the Syrian Observatory for Human Rights.

The Britain-based watchdog also reported that 28 students were wounded, three of them critically.

Activists said the raid was carried out in response to daily anti-regime demonstrations at the university in Syria’s second largest city.

“Security forces stormed the campus in large numbers at night and opened fire during a large student demonstration calling for the fall of the regime,” Halabi said.

As many as seven people have been killed by the fire of Syrian forces across the country on Thursday, Al Arabiya reported citing activists at the Syrian Revolution Commission.

Massive protests were reported in several neighborhoods in the capital Damascus, the biggest of which was reported in al-Salheiya region, Al Arabiya reported citing Syrian activists.

Random shootings were reported in al-Hamama village in Idlib, activists said, and mortar shells hit Rastan in Homs.

Top U.S. senator visits refugees in Lebanon

Violent crackdown continued in Syrian cities as an influential U.S. senator expressed support for the Syrian opposition Wednesday, following meetings with top Lebanese officials and a visit to Syrian refugees in northern Lebanon.

“I and a number of my colleagues in the U.S. Senate are very concerned about the conflict in Syria and about the atrocities that are being carried out by the government forces,” Joseph Lieberman told reporters after meeting Prime Minister Najib Mikati.

“I’m also concerned that people in the region and throughout the world have not done enough to be supportive of the opposition in Syria to Assad,” he said in reference to Syrian President Bashar al-Assad, according to AFP.

The independent senator, a member of the Senate Armed Services Committee, is hawkish on national security and, along with Republican John McCain, has advocated the arming of the opposition against Assad’s regime.

Lieberman earlier Wednesday visited the northern Lebanese region of Wadi Khaled, which is located near the Syrian border and houses the majority of an estimated 24,000 Syrians who have sought refuge in Lebanon.

The senator and his delegation toured the Lebanese-Syrian border, escorted by the Lebanese Army, according to Mahmoud Khazaal, a local official charged with overseeing refugee affairs.

Lieberman met 25 refugee representatives at the official’s home in the border town of Mukaybleh. “The delegation asked whether the aid which reached them was sufficient and promised to provide assistance,” Khazaal said.

The senator said he “respects” the position of the Lebanese government, which is dominated by the Syrian-backed militant group Hezbollah, to “disassociate” itself from the conflict in Syria.

“I couldn’t frankly make the same request to him (Mikati) as I made in Qatar and Saudi Arabia, which is: please help these people in Syria that are fighting for their own freedom,” Lieberman said.

As many as 30 people have been killed by Syrian forces across the country on Wednesday and Syrian rebels killed 15 members of the security forces in an ambush, a monitoring group said, and a human rights organization accused Damascus of war crimes in last month's run-up to a U.N.-brokered truce, according to Reuters.

Most independent media are barred from Syria or have their movements restricted, making it hard to verify such reports.

The United Nations says Syrian forces have killed 9,000 people in a violent crackdown on mass protests that started against Assad in March 2011. The initially peaceful demonstrations have since turned into a bloody guerrilla insurgency.

Damascus says 2,600 personnel have been killed by “armed terrorists.” Since a U.N.-backed ceasefire came into effect on April 12, it has cited rebel assaults as justification of its right to respond to “any violation or attack.”

The United Nations now has 30 blue-helmeted monitors inside the nation of 23 million people, and this week accused both pro- and anti-Assad forces of violating the three-week-old truce.

The truce brokered by former U.N. Secretary-General Kofi Annan has led to a small reduction in the daily carnage, especially in cities were monitors are deployed permanently.

However, New York-based Human Rights Watch (HRW) accused government forces of going on a killing spree in opposition areas as officials in Damascus were sitting down with Annan to negotiate the terms of the truce in March and early April.

In assaults on the northern province of Idlib, troops killed at least 95 civilians -- many of them executed in cold blood -- and destroyed hundreds of homes, HRW said in a report that accused Damascus of war crimes.

Damascus has not commented on the report. It accuses foreign-backed armed groups of being behind the violence.

Syria is gearing up for multi-party elections on May 7 -- part of a political reform package agreed to by Assad as a gesture towards those who want an end to his family’s four-decade grip on power.

And in an apparent concession to the thousands of Syrians who have avoided military service since the violence began, Assad announced an amnesty for draft-dodgers.

Western states do not set much faith in either the ceasefire or reform process.

Paris has called for U.N. sanctions, but the West can do little given the diplomatic cover Syria enjoys at the Security Council from China and Russia.

Moscow says the rebels are mainly to blame for the continued violence and issued a statement on Wednesday condemning “terrorists” for “a large-scale campaign to destabilize the situation and disrupt ... Annan’s plan.”

Western states are wary of military intervention along the lines of last year’s air campaign that helped topple Libya's Muammar Qaddafi because of the greater diplomatic and military complexities of tackling Syria, as well as the potential spillover effects on a volatile Middle Eastern neighborhood.